Hi Eude
I gave both a good run. I didn't try two of the Mi10s, but I plumped for the Mi12 in the end anyway as it was just bigger sounding and had a lovely smooth tweeter in it. The Mi10 sounded boxy to me, which I guess is unsurprising as it is not much bigger than a cardboard box anyway!
There are two Mi12s for sale here on BC at the mo, so you could sort yourself pretty cheaply if you want to go that route.
Cheers
Gareth